To John Franklin
ALS: New York Academy of Medicine
Philada. Dec. 8. 1752
Reflecting yesterday on your Desire to have a flexible Catheter, a Thought struck into my Mind how one might possibly be made: And lest you should not readily conceive it by any Description of mine, I went immediately to the Silversmith’s,1 and gave Directions for making one, (sitting by ’till it was finish’d), that it might be ready for this Post. But now it is done I have some Apprehensions that it may be too large to be easy: if so, a Silversmith can easily make it less, by turning [written above: twisting] it on a smaller Wire, and putting a smaller Pipe to the End, if the Pipe be really necessary. This Machine may either be cover’d with a small fine Gut first clean’d and soak’d a Night in a Solution of Alum and Salt in Water, then rubb’d dry which will preserve it longer from Putrefaction: then wet again, and drawn on, and ty’d to the Pipes at each End where little Hollows are made for the Thread to bind in and the Surface greas’d: Or perhaps it may be used without the Gut, having only a little Tallow rubb’d over it, to smooth it and fill the Joints. I think it is as flexible as could be expected in a thing of the kind, and I imagine will readily comply with the Turns of the Passage, yet has Stiffness enough to be protruded; if not, the enclos’d Wire may be us’d to stiffen the hinder Part of the Pipe while the fore Part is push’d forward; and as it proceeds the Wire may be gradually withdrawn. The Tube is of such a Nature, that when you have Occasion to withdraw [it] its Diameter will lessen, whereby it will move more easily. It is also a kind of Scrue, and may be both withrawn and introduc’d by turning. Experience is necessary for the right using of all new Tools or Instruments, and that will perhaps suggest some Improvements to this Instrument as well as better direct the Manner of Using it.2
I have read Whytt on Lime Water.3 You desire my Thoughts on what he says. But what can I say? He relates Facts and Experiments; and they must be allow’d good, if not contradicted by other Facts and Experiments. May not one guess by holding Lime Water some time in one’s Mouth, whether it is likely to injure the Bladder?
I know not what to advise, either as to the Injection, or the Operation.4 I can only pray God to direct you for the best, and to grant Success.
I am, my dear Brother Yours most affectionately
I find Whytt’s Experiments are approv’d and recommended by Dr. Mead.5
Addressed: To Mr John Franklin Boston Free B Franklin
Endorsed: Br Benj Dec 8 1752
1. Philip Syng?
2. BF’s letter conveys an erroneous impression that the instrument was of his own invention. It was, however, of a type in common use abroad: Francesco Roncalli-Parolino made a flexible catheter about 1720 by twisting a thin bar of silver into a spiral and covering it with fine silk, which he then dipped in resin and coated with Nuremberg plaster. Bigelow, Works (Federal edit., 1904), XII, 260 n. The basic design is still practical. Harold Lamport and Herbert F. Newman, “A Critical Appraisal of Methods for Disruption and Extraction of Urinary Calculi, especially with Ultrasound,” Yale Jour. of Biol. and Med., XXVII (1955), 417 n.
3. Robert Whytt’s essay was first published in the Edinburgh Medical Society’s Essays and Observations, V, pt. 2 (1743); “corrected and enlarged,” it was separately published as An Essay on the Virtues of Lime-Water in the Cure of the Stone (Edinburgh, 1752), with an appendix containing Horace Walpole’s account of his own case. Whytt was later president of the Royal College of Physicians of Edinburgh. DNB. Other diets proposed for dissolving urinary calculi included ashes, egg shells, meat, and various combinations of hope and humbug.
4. Eighteenth-century attempts to dissolve vesical stones by injecting liquids, such as vinegar (acetic acid), into the bladder through the urethra, or to remove them by surgery, were always painful, often harmful, and sometimes fatal. BF himself later used the solvent of Alexander Blackrie. DNB; George W. Corner and Willard E. Goodwin, “Benjamin Franklin’s Bladder Stone,” Jour. Hist. Med., VIII (1953), 359–77.
5. Richard Mead, Medical Precepts and Cautions (London, 1751), pp. 200–3.